* {
    margin: 0;
    padding: 0;
}

#header {
    width: 100%;
    background: #ffffff;
    box-shadow: 2px 3px 5px;
    height: 60px;
    padding: 10px 0;
    background-color: rgb(24, 131, 209);
}

.header {
    width: 1200px;
    margin: auto;
}

.header-logo {
    float: left;
}

.header-nav {
    float: right;
}

.header-logo img {
    float: left;
    width: auto;
    height: 60px;
}

.header-logo h4 {
    float: left;
    margin-left: 15px;
    height: 60px;
    line-height: 60px;
    font: size 22px;
    font-weight: normal;
    letter-spacing: 2px;
}

.header-nav ul li {
    float: left;
    height: 60px;
    line-height: 60px;
    margin: 0 20px;
}

.header-nav ul li a {
    text-decoration: none;
    color: #333333;
}

body {
    font-size: 20px;
}

.header-nav ul li a:hover {
    color: rgb(193, 222, 30);
}

.header-nav ul .aaa a {
    color: rgb(154, 220, 31);
}

table {
    text-align: center;
    width: 100%;
}
.banner{
    width: 1200px;margin: 20px auto;display: flex;justify-content: space-between;
}
.banner-left img{ width: 500px;height: 380px;object-fit: cover;}
.banner-left{ width:500px;height:380px;}
.banner-right{width:380px;}
.banner-left img{box-shadow: 2px 3px 5px;}

td:nth-child(2n){
    background-color: plum
}
td:nth-child(1){
    background-color:skyblue
}
footer{
    background-color: rgb(84, 37, 154);text-align: center;margin-top: 50px;
}
.bbb img{box-shadow: 2px 3px 5px;}